High impedance absolute telephone line voltage measurement...
Impedance measuring apparatus for R.F. baseband signals over two
In-line telephony data protector with line condition announce
Integrated ring sensor with fault detection
Intelligent line testing
Line probe signal and method of use
Line sharing multipoint POTS splitter with intelligent...
Line shunt and ground fault apparatus method
Line testing in a telecommunications network
Line testing method and apparatus therefor
Long-distance transmission system and device
Loop certification and measurement for ADSL
Loop certification and measurement for ADSL
Loop loss measurement and reporting mechanism for digital...
Loop loss measurement and reporting mechanism for digital...
Maintenance termination unit
Mechanism for controlling operation of telephone metallic loop m
Metallic testing of a subscriber loop that provides both...
Method and apparatus for determining the value of analog voltage
Method and apparatus for generating an audible tone in DSL...